Gearing for lathes.



A. W. WHITCOMB.

GEARING FOR LATHES.

APPLICATIQN FILED NOV. 27, 1914.

Patented Feb. 15, 1916.

3 SHEETSSHEET 1.

Razz/{v77 A. W. WHITCOMB.

(BEARING FOR LATHES.

APPLICATION FILED NOV. 22, 1914.

Patented Feb. 15, 1916.-

3 SHEETS-SHEET 2 A W. WHITCOMB.

GEARING FOR LATHES,

APPLICATION FILED NOV. 21. 1914.

1,171,995. Patented Feb. 15,- 1916.

3 SHEETSSHEET 3.

THE COLUMBIA PLAN c.

ALONZO w. WI-IITCOMB, or wononsrnn, MassncHUsnrrs.

GEARING FOR LATHES.

Specification of Letters Patent. I Pat t d 15, 1

Application filed November '27; 1914, Serial No. 874,158

To'aZZ whom it may concern Be it known that I, ALoNzo VV VVmr- COMB,a'citizen of the United States, resid orcester' ing at lVorcester, inthe county of l and State of Massachusetts, have invented a new anduseful Gearing for'Lathes, of which the following is aspecification.

This invention relates to a lathe and particularly V to improved devicesfor driving the lead screw thereof. 7 V

in an engine lathe it is necessary to make provision by which the speedof rotation of the lead screw may be varied relative to that of thespindle. To secure this change in relative speed, it has been customaryto pro-l vide a change gear mounted upon a swinging arm and means forangularly adjusting the swinging arm so that the particularv change gear1n use maybe brought into mesh with the pinion upon the lead screw. Withthis arrangement, it is necessary to adjust the change gear studupon'the swing: ing arm for each different change gear, in addition toadjusting the arm itself with relation to' the lead screw pinion.

t isone object of my inventionto improve upon this construction bymounting the change gear upon an intermediate shaft which rotatesinfixed bearings. With this arrangement there is no adjustment of theshaft which carries the change gear audit is merely necessaryto changethe position of the swinging arm in order to bring the driving gearsinto proper relation. It is found, however, that this arrangement aloneis not practicable where a wide range of feeds is desired, as changegearsof prohibitive size.

would be required.

Accordingly, it is a further object of my invention to provide means forchanging the speed of rotation of the lead screw rela- "tive to theintermediate shaft.

In the preferred form of my invention'l provide a set of gears upon thelead'screw and a correspondmg set of gears slldable upon and rotatablewith the intermediate shaft. \Vhen three gears are provided upon providean improved detachable fastening for securing the change gear upon theintermediate shaft.

l/Vith this and other objects in view, my

invention comprises certain devices, ar-

rangements and combinations of partsas will be hereinafter describediandmore particularly pointed out in the: appended claims.

A preferred form of my invention is shown in the drawings in which, i

Figure 1 is a side. elevation of a portion of a lathehaving my improveddevices'em bodied'therein; Fig. 2 is a left-hand end elevation of theportion of the latheshown f in Fig. 1; Fig. 3 is a view similar to Fig.2;

with the gears .insa different position and the V i gear covers removed;ig. 4 isan enlarged detail view of a portion of the gear connectionsbetween the spindle and the intermedi-f ate shaft; Fig. 5isa sideelevation partially in section ofthe'parts shown in Fig. 4:; Fig.

6 is a detail sectional view taken along the line 6 6 in Fig. 5; Fig. 7is an enlarged" front elevation of the'drivingconnections,v

between the intermediate shaft and the lead screw Figs. 8 and 9 aredetail views of the devices for sliding the "shift'gearsupon theintermediate shaft,.'and Fig. '10 *is an en- :8

larged detail view of the locking plate for detachably securing thechange gear upon the intermediate shaft. v

I have shownmy improved device as applied to an engine latheof ordinaryform having abed 10 supported upon legs 11am; provided with an oil pan12 The ihead-I stock 13 is mounted upon the bed and prothe cone drivingpulley 15, the face plate vides bearings for "the spindle" 1d carrying15 and the spindle 14; A lead screw '18 is I mounted in the" usualposition at the front of the bed, the left-hand end of the lead'screwextending into a shift gear] box 119. The

. lead screw is supported in beaLrin gsf2O and. 21 (Fig. 7 at each sideof the 'bOX 19. A

plurality of gears 22, 23 and 24: are fixed to the lead screw within thebox 19. .An intermediate shaft 25 is mounted in bearings above the leadscrew 1 8'and supports a plu-' rality ofshift gears 26,27 and 28 withinthe. These gears are secured to} gether and are 'slidable along theshaft 25,

shift gear box.

while at the same time they are keyed, or otherwise secured, to rotatewith the shaft.

The front plate of the gear boXf'19' is provided with a longitudinalslot 3 0 in which. is fitted a sliding block 31 having inwardlyprojecting lugs 32 adapted toextend upon:

tate at higher speed thanthe intermediate shaft. When'the block is movedto the left,

the gear 26 will mesh with the gear 22 and the shafts will rotate atsubstantially the same speed, while movement of the block to the rightwill cause the gear 28 to mesh with the gear 24-, which combinationcauses the lead screw 'to-rotate much slower than the shaft 25. I

In order to facilitate the meshing of the gears 27 and 23, Iprovide thepivoted stop 35 shown in Figs. land 8. If the block is in the positionindicated as No. 1 insaid figures and the, operator wishes to remove theblock to position No. 2, he moves the pivoted stop to the position shownin Fig. 8 in which position it engages the right-hand end of the plate33 and positions the sliding block so that the gears 2'7 and 23 are inoperative positiona If the block is in position No. 3 and it isdesirable to move it to position No. 2, the pivoted stop 35 is moved tothe position shown in Fig. 1.

At its left-hand end, the intermediate shaft 25 is provided with meansfor adjustably securing any one of a series of change gears 40 thereon.The means for securing the gear in place is clearly shown in Fig. 10 andcomprises a locking plate 41 having a longitudinal slot 42 therein, andalso provided with a plurality of notches 43 in its outer edge. A stud44 is mounted in ears formed on the end of the shaft 25 and'extendstransversely through the slot.

42. I'Vhenihe locking plate is positioned as shown in full lines in Fig.10, a change gear 40 may be readily passed thereover, but when the plateis placed in the position indicated in dotted lines in said figure, thegear is securely held uponthe shaft.

In order to retain the plate in either one of the positions indicatechIprovide a ball 45 mounted to slide longitudinallyin the recess 46 formedin the end of the shaft 25.

A spring 47 positioned within. the recess.

51 is mounted upon. a fixer stud 52 on the head-stock13. Reversing gears53 and 5. provide a driving connection between the lVith this gear covershown in'the drawings.

meshes directly with the pinion 50, while in.

the reverse position the gear 53-meshes with the gear 50 andthe gear 54Lacts as an inter mediate gear in, the usual manner. A dew pending arm 56is also mounted to swing about the axis of the stud 52, the arm beingprovided with a hub 57.11aving a bearing in the head-stock 13. j

The arm 56 is held in adjusted angular position relative to thehead-stock by the binding device shownin Figs. 5 and 6. This devicecomprises a bushing- 5S having a por-v tion of its inner end formed tocorrespond 1' ]Il curvature to the surface of the hub :57' and having abinding screwv 59 extending therethrough into the l1ead-stoclr13...

Tightening of the binding screw'forcesthe bushing against the hub 57,thus clamping the hub securely;withinthehead 13., The bushing 58 alsocarries a pin 60 positioned to cooperate with a groove 61 in the hub 57,thereby preventing longitudinal displacement of the hub. in its recess.bored out through its center to provide a: bearing for the stud 52 andis also provided 1' with a set screw 62 extending into a groove 63 inthe stud 52. and preventing. longitudinal movement of the stud relativeto s the hub 57.

The entire driving connection betweenthe I pinion 60 and the change gear40 may be removed by loosening the binding bushing 58, while the gearel,the, reversing gears 53 and 54, and the reversing plate 55 may be Thehub is i removed from the arm 56 by looseningthe 1 If the change inspeed ratio is beyond the limits of the change. gears provided. theshift gears in the b03019 may be adjusted to secure the desired ratio.

It has been shownthat the gear 40 is the only gear to be changed in:securing adesired feed ratio. T he necessary angular adjustment of thear1np56is also much reduced by the use of the shift gears described; Iam thus enabled to use the very compact gear cover compris'esa fixedcasing 70. (Figs. 1 and 2) formedof one or more parts and This fixed tothe head 13. Upon the casing 70 there is pivotally mounted a cover plate71 secured thereto by a stud 72 and having a .projection 73 engaging astop 74: upon the casing 70. l/Vhen a change is to be made inthe gear40, the cover 71 may be swung up ward until it engagesa stop 75 upon theY casing 70.

Having thus described my invention, it will be evident that many changesand modifications can be made therein by those skilled in the artwithout departing from the spirit and scope thereof as set forth in theclaims, and I do not wish to be limited to the details herein disclosed,but

lVhat I do claim is 1. In a lathe, a combination, a head stock, aspindle, a lead screw, and an intermediate shaft positioned parallel tosaid lead screw, a pinion on said spindle, a changegear' on saidintermediate shaft, driving connections from said pinion to said changegear, and a cover for said gears comprising a casing fixed to thehead-stock and having an opening therein concentric with saidintermediate shaft and change gear, a cover plate for said opening, andmeans to support the cover plate in position to close said open- 1n In alathe, in combination, a lead screw, an intermediate shaft paralled tosaid lead screw, a set of gears fixed to said lead screw, a set of gearsslidableon said intermediate shaft, a box inclosing said sets of gearsand having a slot in the front thereof, a gearshifting block slidable insaid slot, and 'a reversible stop movable into position to stop saidblock in mid-position when moved ineither direction.

3 .In a lathe, in combination, a spindle, a plnion on said spindle, alead screw, an intermediate shaft positioned parallel to said lead screwand rotatable in fixed bearings,

shiftable gear connections between. said intermediate shaft and saidscrew, a change arm and the entire driving connections from said pinionto said change gear being re- .movable as a unit from saic l lathe.

4. In a lathe, in comblnatlon, a spindle,'a

pinion on said spindle, a lead screw, an intermediate shaft positionedparallel to said lead screw and rotatable in fixed bearings, shiftablegear connections between said 1ntermediate shaft and said screw, achange gear on said shaft, an arm movable about a fixed center, a drivengear rotatable about the pivotof said arm, reversible means to drivesaid gear from sald p1n1on,'and drivlng connections on said arm for drivng said change gear from said drivengear, the

driven gear and the reversible connections.

from said pinion to said gear being supported upon a single stud andremovable as a unit from said lathe. V

In testimony whereof I have hereunto set my hand, in the presence of twosubscribing witnesses.

ALONZO w. wHITooMBj Witnesses: r

B; ALFRED WHEELER, CLARENCE F. WHITE.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. C.

